Detecting means for presses



Sept. 14, 1943. E. v. CRANE DETECTING MEANS FOR PRESSES 2 Sheets-She et 1 Filed Jan. 7, 1941 Z Z MW M M m W 4 Sept. 14, 1943. E. v. CRANE DETECTING MEANS-FOR PRESSES 2 Sheets-Shet 2 Filed Jan. '7, 1941 INVENTOR. [DWA/PD V CRANE.

(15;, JJMMW v ATTORNFYS.

Patented Sept. 14, 1943 "UNlTED sr rs-s- PATENT OFFICE Ed ard v. Crane, Brooklyn, N. Y.,'assignor 10 E. W.'Bliss'.Company, Brooklyn, N. Y.',' a corporation of Delaware Application January), 1941,]Sriai m me This invention relates, as indicated,;to detect; ing means for presses, but has reference more particularly to an electrically operated protectivedetector for .use in connection with presses in which progressive dies are employed.

Itis customary in feeding strip to presses for forming by progressive dies, for the operator to visually inspect thestrip as it is fed in order'to insure that the .stripis fedforwardly just the' right amount at each step, to prevent damage to the dies orspoilage of elementsalready acted upon by the dies. At slow speeds of the press,

this visual inspection. isfeasible but neverthe less is not dependable, since it relies to too great an extent on the human factor or element. In presses used at high speeds manual control is not possible and automatic means of control must be provided.

It has been a primaryfobject of the present invention, therefore, to provide detecting means which will insure accurate feeding of the strip. during high speed operation of the press, and which, therefore, will result in elimination of waste or spoilage of the strip.

A further object of the invention has been to provide a detector which is inexpensive and simple in construction, and which can be readily attached to and removed from a press without disturbing, to any appreciable extent, the press as a whole.

To the accomplishment of the foregoing and related ends, said invention, then; consists ofthe means hereinafter fully described and par ticularly pointed out in the claims; the annexed drawings and the following description setting forth in detail certain structure'embodying the invention, such disclosed structure constituting,

which the however, but one of various forms in principle of the invention may be used.

In said annexed drawings: Fig. 1 is a plan view illustrating a as it passes through a press, in which are incorporated progressive dies, and the detecting means of'the present invention associated'with saidpress; p

Fig. 2 is an enlarged plan view of the detector; Fig. 3 is a front elevation of the detector; Fig. 4 is a side elevation of they detector in its normal condition and showing the means for actuating. the. detector; f a Fig. 5 is a view similar to Fig. 4, but showing the manner in which the detector operates when 7 the striphaslaeen properly fed;

m'etal strip,

the manner in which the detector operates when the striphas been improperly fed; and;

Fig. 7. isa view similar to Fig. 4, but showing a modified former the detector.

The detector comprises a base I0 having a pair of spaced upstanding ears II in which is mounted a pin 12. This base is adapted to be mounted on theidie shoe or the bolster of the press. u e

Mounted for pivotal or rocking movement aboutthe pin I2 is a; member l3, a portion I4 of which constitutes a platform for a normally open micro-switch l5, secured to such platform as by means of screws l6, and provided with the usual plug connection I! for a 110 or 220 volt line.

Secured to the'member l3, as by means of cap screws I8, is a cam plate 19 having abeveled edgeZO at the rear fora purpose to be presently described. The plate l9 has slots 2| therein throughwhich the screws 18 extend, these slots extending in adirection to permit adjustment of the plate in, a forward and rearward direction,

member 13; the, spring tendsto bias said member in clockwise direction, but is counteracted by a screw 2, .which is secured to member I3 near the other end thereof and, is adapted to abut the base plate 10. The major portion .of spring 22 is disposed within a socket; in the member .13 and is therefore concealed, as well as prevented from shifting laterally. A tains the scre w 2 3 in any adjusted position.

Pivotally mounted on the pin 12 between the ears H of the base IO'is a pilot holder 24, preferably made of aluminum, in which is mounted a feeler '25, which projects forwardly from the holder and is provided with a down-turned portion 26, terminating ina finger ZT'of reduced diameter. The feeler 25 is adjustable relatively to its holder, and is maintained'in adjusted position by means of a set screw 28.

The holder'M-is provided with an upstanding ear '2'9, between which and the micro-switch I5 is interposed-a coil spring 30.. Extending through said ear 29, in alignment .with said spring 39, is an adjustable contact screw 3|, maintained in adjusted position by means of a lock-nut 32.

lock-nut 24a main- The shank of this screw is adapted, at times, to

actuate the switch-actuating terminal 33 of the used i a pusher rod 35 having a beveled lowerv j the detector is adapted for use with specially end 36. l

The use of the detector will now be described. The strip S is intermittently moved through the press so as to be operateddupon by means of dies progressively arranged in the press. In one operation, for example (see Fig. 1), the perforations ancl notches or recesses 2 of two different commutator elements will be punched out. The strip will then be moved sufficiently to bring these parts of the strip into position for operation upon by a second set of dies which punches out a portion of the strip definedbythe opening 3, which portion contains the perforations I, and, at the same time, punches out a ring-shaped piece of metal, defined by the opening 4, which piece of metal has the notches or recesses 2.

In order to insure that the strip S will be moved the exact distance necessary between the suc'-\ feeding mechanism and the feed is momentarily stopped as the perforations and recesses2 are punched outof the strip. The strip is then moved forwardly to a position'in which the portions of the strip defined by the openings 3 and 4 are punched out, this position being determined by the, opening 5, which, if in proper position, receives the finger 2'! ofthe pilot 25. As the punch plate 34v descends to punch out the aforesaid portions of the strip, the pusher rod 35 simultaneously descends, and thebeveled end 36 of the latter engages the beveled edge of the plate I9, thereby rocking the member I3 about the pivot pin I2. At the same time, the micro-switch I5 is rocked in the same direction as the member I3, and the switch, through the intermediary of the switch finger 33, screw 3I, and holder 24, causes the feeler to move downwardly towards the strip S.

If the opening 5 is in the. proper position to receive the feeler finger 21, such finger will enter the said opening, as illustrated in Fig. 5, and the micro-switch circuit will not be disturbed, the

press continuing to operate in the normal manner.

If, however, the opening 5 is not in a position to receive the detector feeler 21, such feeler, as the pilot 25 moves downwardly, will engage the upper surface of the strip S, a shown in Fig. 6,

It is to be underjusted to proper position before resetting the micro-switch and starting the press.

It will be apparent from the foregoing description that the use of the detector, in that it checks the feed stroke accuracy of the strip at each press stroke, will permit faster press operation, and will permit speed of the press to be increased without making it necessary or difficult for the operator to determine what is taking place as such speeds are increased.

In that form of the invention shown in Fig. 7,

timed feed mechanisms. For instance, if feeding takes place principally on the up-stroke of the press, referred to in the claims a the return stroke, then detection may take place as the feed is completed or during the return stroke of the press; In normal operation feed is completed on the advancing strokeof the press and is followed by the detection operation. For this purpose, the plate I9 is mounted for pivotal movement, and ha two beveled edges 20 and 20", the first of which is adapted to be engaged by the 36' of the pusher rod 35, and the second of which is adapted to be engaged by the edge 36" of said rod.

A a part of the present invention there is involved a method of detection which is accom-v plished by forming a shoulder on the strip being fed and then using that shoulder to control the operation of the feeler member. In the present disclosure the hole 5 i first pierced in the strip as it is fed to the press and then that hole 5 is used in conjunction with the feeler 25 to govern the feeding of the press through successive stages.

It will be apparent that the present invention is not confined in it use to presses, but may be used in other mechanisms where a fabricating step of similar nature is performed on a piece of material. It follows from the description that the feeler finger or member may be adjusted to operate at any time in the stroke of the mechanism with which it cooperates, thus providing a latitude in operationhitherto unattainable. Likewise it will be seen that I have provided asimple mechanism for detection which may be readily attached to existing devices, and need not be built therein asan inherent part of the whole.

Other modes of applying the principle of my in vention may be employed instead of the one explained, change being made as regard the Stl'UC-r ture hereindisclosed, provided the means stated by any of the following claims or the equivalent of such stated means be employed.

Itherefore particularly point out and distinctly claim as my invention: 4

l. In a mechanism for performin a plurality of successive fabricating operations on a stripof material, a detecting means comprising a switch adapted to control the transmission of an electrical impulse, a shiftably mounted feeler member responsive in movement to the position of aid strip with respect thereto to actuate said switch, means operative in timed relation to the operative cycle of said mechanism to actuate said feeler member and means to vary the time of actuation of said feeler to take place'at anytime in -the operative cycle of said mechanism.

2. In a mechanism for performing a plurality of successive fabricating operations in advancing and returning cycles on a strip of material, at detecting means comprising'a'switch adapted to control the transmission of an electricalimpulse, a shiftably mounted feeler member responsive in movement to the position of said strip with respect thereto to actuate aid switch, index means on said strip to engage with said feeler member when the strip is properly positioned, means operative in timed relation to the operative cycle of said mechanism to actuate said feeler member and mean to vary the time of actuation of said feeler to take place at any time in the advancing portion of the operative cycle of said mechanism.

3. In a mechanism for performing a plurality of successive fabricating operations in advancing and returning cycles on a strip of material, a detecting means comprising a switch adapted to control the transmission of an electrical impulse, a shiftabl mounted feeler member responsive in movement to the positionof said strip with respect thereto to actuate said switch, index means on said strip to engage with said feeler member when the strip is properly positioned, means operative in timed relation to the operative cycle of said mechanism to actuate said feeler member and means to vary the time of actuation of said feeler to take place at any time in relatively to said base, means to actuate said the returning portion of the operative cycle of said mechanism.

4. In a mechanism for performing a plurality of successive fabricating operations on a strip of material, detecting means comprising a switch adapted to control the transmission of an electrical impulse, a pivotally mounted feeler mem ber responsive in movement to the position of said strip with respect thereto to actuate said switch, index means on said strip to engage with said 5. In a press embodyinga-punch with a reciprocating stroke for performing a plurality of successive fabricating operations on a strip of material and having a ram for driving said punch, a detecting means comprising a switch adapted to control the transmission of an electrical impulse, a shiftably mounted feeler member responsive in movement to the position of said strip with respect thereto to actuate said switch, index means on said strip to engage with said feeler member when the strip is properly positioned, means carried by said ram and operative to actuate said feeler member, a strip engaging finger on said member and mechanism including a wiper cam operatively connecting said memberv and said punch at a predetermined time in the cycle of operation of said press to impart a moswitch-carrying member in timed relation to the operating cycle of said mechanism and means for maintaining said member normally immovable with respect to said base, said means comprising a spring interposed between said base and member at one side of the base, and a screw interposed between said base and member at the other side of said base.

7. In a mechanism for performing a plurality of successive fabricating operations on a strip of material, a detector comprising a base, a switchcarrying member mounted for pivotal movement relatively to said base, said member having a cam plate mounted thereon, and means connected to said mechanism for actuating said cam in timed relation to the operating cycle thereby moving said member toward engagement with said strip.

8. In a mechanism for performing a plurality of successive fabricating operations on a strip of material, a detector comprising a base, a member mounted for pivotal movement with respect to said base, a micro-switch mounted on said member, a second member shiftably mounted for movement relative to said base, but independently of the movement of said first-namedmemher, a feeler'secured to said second member, said feeler being capable of engaging with indicia means on said strip when the strip is properly positioned. I

, 9. In a mechanism for performing a plurality of successive fabricating operations on a strip of material, a detector comprising a base, amember mounted for pivotal movement with respect to said base, a cam plate secured to said member,

a micro-switch mounted on said member, said switch having a finger projecting therefrom, a. second member shiftably mounted for movement with respect to said basebut independently of said first-named member, means mounted on tion to said finger shorter than the stroke of i 

